Follow up of retinal nerve fiber layer thickness with optic coherence tomography in patients receiving anti-tubercular treatment may reveal early optic neuropathy.

PURPOSE: To evaluate the effect of anti-tubercular treatment on retinal nerve fiber layer (RNFL) thickness and the efficiency of optic coherence tomography (OCT) on early diagnosis of optic neuropathy.

METHODS

Twenty patients diagnosed with either pulmonary or extra-pulmonary tuberculosis which were treated with anti-tubercular treatment (isoniazid (INH), rifampicin, ethambutol (ETM), and pyrazinamide) were enrolled in the study. RNFL thicknesses of the patients were measured via OCT, at baseline (before starting anti-tubercular treatment) and after the two-month treatment period. Standard ophthalmologic examinations were also performed.

RESULTS

Compared to baseline values, after the two-month treatment period, thinning was detected in the right eye's average and superior quadrant RNFLs (p = 0.024 and p = 0.006 respectively) and in the left eye's average, superior quadrant, and inferior quadrant RNFLs (p = 0.001, p = 0.008, p < 0.001, respectively).

CONCLUSION

We displayed that patients receiving INH and ETM, which were the basic medicines of anti-tubercular treatment, experienced thinning in RNFL after the two-month treatment period. Patients receiving these drugs can be followed via OCT in terms of reduction in RNFL thicknesses for early diagnose of INH and ETM toxicity.